Catena Aurea on John 1:29–31: Augustine of Hippo

If the Lamb of God is innocent, and John is the lamb, must he not be innocent? But all men come of that stock of which David sings sorrowing, Behold, I was conceived in wickedness. (Ps. 51:5) He then alone was the Lamb, who was not thus conceived; for He was not conceived in wickedness, nor in sin did His mother bear Him in her womb, Whom a virgin conceived, a virgin brought forth, because that in faith she conceived, and in faith received.